Automatic fuel control for scarfing torches and the like



Dec. 10, 1940. w. VAN TRIEST AUTOMATIC FUEL CONTROL FOR SCARFING TORCHES AND THE LIKE Filed Aug. '7, 1939 Patented Dec. 10, 1940 UNITED STATES ao'rom'rrc FUEL ooN'rnoL non some 'rononns AND THE mm William Van Triest, Pittsburgh, Pa. Application August 7, 1939, Serial No. 288,892

1 Claim. (Cl. 15827.4)

The present invention relates to the automatic control of the fuel and oxygen supplied to scarfing torches and the like.

An object of the present invention is to provide automatic means for substantially shutting off the supply of fuel gas when the scarflng oxygen is fed to the torch nozzle and re-establishing said fuel supply when the scarflng oxygen is shut off.

Another object of the present invention resides in maintaining a small amount of fuel g s to provide a pilot flame for the preheat treatment of the metal (lining the time that the pure oxygen is being fed for the scarfing operation so that upon shutting off of the feed of oxygen,

the preheating flame automatically returns to the torch nozzle without further adjustment.

Other objects and advantages will become apparent as the descripti'vn proceeds and reference is had to the acompanying drawing, in which:

Figure 1 is a side elevation of the embodiment of the control mechanism for the preheating flame in combination with the control mechanism for encircling the oxygen stream;

Figure 2 is a section on line 11-11 of Figure 1;

Figure 3 is an enlarged detailed section of the attachment to the end of the nozzle; and

Figure 4 is an end view of the fitting attached to the burner nozzle.

In the drawing, a commercial scarfing torch of conventional design is diagrammatically shown at 2. This torch includes a burner tip 3 at one end and a handle 4 at the other end, between which are positioned the conventional 5 tubes for conveying oxygen and fuel gas for the preheating flame and the main supply of. oxygen to the burner tip 3 for removal of the surface imperfections in the material being scarfed.

As shown in Figure 3, the large central hole 5 is the passage for the main flow of pure oxygen used for scarflng after preheating of the metal surface has been accomplished; The flow of the pure oxygen through its tube to the burner tip 3 is controlled bythe valve lever 6 pivotally supported, in any conventional manner, on the handle 4. Surrounding the large central hole' 5 in the burner tip 3, is a circle of small holes or passages 1 serving as ports for passage of the mixture of fuel gas and oxygen used to make up the preheating flame. This mixture of fuel and omen passing through the small holes 1 is regulatedby adjusting the needle valve wheels diagrammatically shown at 8 and 9, so that the proper mixture may be supplied to the burner tip for'preheating the steel prior to the application of the main supply of oxygen passing through the opening 5.

Heretofore, the preheat mixture of fuel gas and oxygen fed to the circle of small holes in the burner tip 3 aforementioned, has been con- 5 tinued while the main scarflng stream of pure oxygen is being supplied through opening 5 so as to have the preheating flame ready for the next cut.

This has been found to be uneconomical and 10 the present invention provides means for overcoming this objection by controlling the ,fuel supply. There is positioned between the pure oxygen control mechanism and the fuel gas hose connection ill, a spring loaded plunger valve 15 mechanism indicated generally at ll, said spring loaded plunger valve mechanism being of conventional construction and including the valve lifting rod l2 projecting from said plunger valve mechanism II to be engaged by the lever arm 20 M. This lever arm I4 is pivotally connected, in any conventional manner, to the body of the plunger valve mechanism H and is likewise pivotally connected to an adjustable mechanism I5 which, for the purpose of illustration, has been 25 shown as comprising a turnbuckle arrangement. The other end of said adjustable connection or turnbuckle is connected to the end of the scarfing oxygen valve lever B. When said lever 6 is depressed to open the valvesupplying the pure oxygen to the main passage 5, for scarfing the surface defects of the material being treated, the fuel gas being supplied through said ports I, for the preheating treatment of the surface of the material to be scarfed, is substantially shut 011. 35

Only a suflicient quantity of the fuel gas is permitted to pass through the;supply pipe for the purposes of maintaining a pilot flame. When the supply of pure oxygen is shut off, preparatory to making another cut in the metal, the a lever 6 is released and, due to a conventional design of spring action (not shown) is returned to its original position. In so doing, the valve within the valve mechanism H is opened to reestablish the supply of fuel gas to the burner tip and restore the preheating flame at the torch tip ready for the next cut.

The valve H is positioned rearwardly of the handle 4- and substantially in alinement therewith. Also, the adjustable linkage IE is disposed 5o rearwardly of the handle, whereby said valve and linkage comprise virtually a simple extension of the torch proper without interfering projection and without rendering the assembly bulky'and unwieldy. Further, the disposition of the valve 1 and its connection with the torch proper does not destroy the balance of the assembly.

Secured, in any conventional manner, upon the end of the burner tip 3 is a fitting l6 having an extension [1 formed thereon, which extension is provided with a' central opening I8 to which is connected a pipe I9. A distributing chamber 20 is provided within the interior portion of said fitting l6, which distributing chamber surrounds ,2 the outer periphery of the burner tip 3. A p111 rality of equally spaced channelways 2| are formed upon the inner periphery of the fitting It so thatsaid channelways-2| extend from the end of said fitting inwardly to the distributing chamber 20 in order to establish communication between said distributing chamber and the end of the fitting I 6. The end of said fitting IB is provided with a hardened steel wearing ring 22.

The other end of said pipe I9 is connected, in

any conventional manner, to a compressed. air

supply line 23. A clamp 24 is secured to the handle 4 of the torch and supports, in any conventional manner, a compressed air valve regulating mechanism of conventional design and generally indicated at 25. This compressed valve controlling mechanism includes 'a lever 26 for opening and closing the valve to supply compressed air through the pipe IB into the opening l8 for circulation around the distributing chamber 20. Thedistributed compressed air passes through the respective circumferentially of pure oxygen, the pure oxygen is confined to the furrow or out being made, prevents the formation of a wash or fin at the sides of the furrow and reduces any tendency of the pure oxygen to flare out and waste to the atmosphere.

Under the present invention, there is provided a torch in which there is a reduction of the heat generated in the scarfing operation, after the preheat period, which will reduce damage to the steel and permit the operator to work' at close range; This heat reduction is the result of the automatic control of the supply of fuel gas to the extent that it is reduced to proportions for a pilotfiame only during the period in which the scarfing oxygen is in operation. Furthermore,

provision is made for more effectively controlling and directing the main oxygen stream used for the scarfing operation, which prevents formation of the usual wash or fin at the sides of the furrow and reduces any tendency of the oxygen to flare out and waste to the atmosphere.

While I have shown and described a specific embodiment of the present invention, it will be seen that, I do not wish to be limited exactly thereto, since various modifications may be made without departing from the scope of the invention, as defined by the following claim.

I claim:

A scarfing torch or the like having a handle, a valve, a lever at the handle for actuating the valve controlling the flow of oxygen to the torch, a fuel gasconnection for the torch, a separate valve between the connection and torch handle for controlling the supply of fuel gas thereto, said fuel valve being disposed substantially in alinement with the torch rearwardly of the said handie, a lever arm carried by the fuel valve for actuating said valve, an adjustable linkage rearwardly of the handle between said oxygen valve lever and the valve lever arm for related movement thereof, said linkage being adjustable for controlling said movement to reduce the fuel gas supply while the oxygen lever is moved to supply oxygen to the torch.

WILLIAM VAN TRIEST. 

